1. Field of the Invention
This invention relates to the field of yarns and fabrics that that are abrasion resistant, and in particular it relates to the field of yarns and fabrics that include abrasion-resistant or cut-resistant fibers.
2. Description of Related Art
Protective apparel such as gloves that include abrasion-resistant or cut-resistant yarn are known in the art. For example, U.S. Pat. No. 5,822,791, discloses a protective glove that is resistant to cuts and to the penetration of liquid. The glove is made from a cut-resistant yarn, such as yarn made from aramid fibers, an intermediate layer that of a natural fiber, and an outer layer of a flexible, elastomeric material impervious to liquid.
U.S. Pat. No. 6,021,523 discloses a hand covering that is heat and abrasion resistant which is made by using a fabric formed from aramid fiber that is wound with a top cover of a yarn of oxidized polyacrylonitrile or polyacrylate. The aramid fiber is conditioned with steam and then with an ignition resistant wax or an organosilicone compound.
Cut-resistant and abrasion-resistant gloves are typically used in applications that subject the gloves to repeated exposure to sharp objects. As a result of this exposure, the gloves have a limited wear life and need to be replaced often.
As shown in U.S. Pat. No. 4,920,000, there have been attempts to improve the abrasion resistance of gloves by blending aramid fibers with other high abrasion-resistant fibers such as nylon. The improvement in abrasion resistance of articles made by such blends of aramid and nylon fibers is proportional to the amount of nylon fibers in the blend, but the improvement in such articles is still limited.
Accordingly, there is a need in the art to provide a yarns and fabrics that have improved cut resistance and abrasion resistance so as to extend the wear-life of articles such as gloves that are made from those yarns and fabrics.
The present invention relates to a yarn having improved abrasion resistance, a fabric that includes that yarn, and a process for preparing the yarn or fabric. The yarn includes (a) aramid fibers and (b) up to 40 weight percent of fibers of synthetic polymers having a melting point between 200 and 300 degrees C., based upon the total weight of (a) and (b) only, the yarn having been heat treated at a temperature below the melting point of the fibers of component (b). The heat treatment of the yarn may take place before or after the yarn is made into a fabric.